The overall goal of this project is to verify the performance advantages of a new dome-swaging ultrafiltration membrane sealing design which has been invented to permit development of a reusable microcentrifugal concentrator system. The system design features have been disclosed in a U.S. Patent Application and optimization results with machine prototypes indicate very competitive filtration rates. Demonstration of overall feasibility for ultimate use in the life science research lab will require construction of R&D molds to produce parts to exact tolerances on key dimensions with mirror-smooth seal surfaces. Creep testing will confirm part stability under high stresses required to reversibly seal membranes without gaskets at accelerations up to 12,000 rcf and beyond. Seal reliability and concentration rate will be tested by measuring permeation of highly-retained proteins, compared to o-ring-sealed reference devices using the same membrane and to commercial disposables of comparable cutoff rating. Performance of a novel skimming deadstop trough with improved sanitary features will be qualified by retentate recovery and carryover. Disposable membranes precut with cutoff-rating-embossed handles will be qualified for ergonomics. Overall system performance and acceptable convenience will be evaluated by independent scientists at several beta sites. PROPOSED COMMERCIAL APPLICATION: A microvolume concentrator with extended component life, permitting simple user assembly and disassembly at the lab bench, could offer a cost and waste-saving alternative to sealed disposable membrane microconcentrators now widely used to concentrate, desalt, buffer exchange and fractionate macromolecules.